Analysis of SSR Performance of TCSC Control Schemes Using a Modular High Bandwidth Discrete-Time Dynamic Model

Subsynchronous resonance (SSR) performance of various control schemes of a thyristor controlled series compensator (TCSC) has been studied in the previous literature using digital simulation based analyses. With the availability of a modular, high bandwidth (six-sample per cycle), discrete-time model of a TCSC, accurate eigen-analysis of a TCSC compensated system has become feasible. Therefore, we revisit the issue of SSR performance in order to gain additional insight provided by this analytical model. We use the model to assess fixed firing angle delay (FFAD) and synchronous voltage reversal (SVR) under different situations. The performance of synchronization schemes and an output feedback subsynchronous damping controller (SSDC) is also evaluated. The derivation of the model is outlined and validated by comparing the results of eigen-analysis with those obtained by detailed digital simulation.